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A Simple VGA Interface
Introduction
The Video Graphics Array (VGA) interface is common to most
modern computer displays and is based on a pixel map, color planes
and horizontal and vertical sync signals. A VGA monitor has three
color signals (red, green and blue) that set one of these colors on or
off on the screen. The intensity of each of those colors sets the final
color seen on the display. For example, if the red was fully on, but
the blue and green off, then the color would be seen as a strong red.
Each analog intensity is defined by a two bit digital word for each
color (e.g. red0 and red1) that are connected to a simple digital to
analog converter to obtain the correct output signal.
The resolution of the screen can vary from 480320 up to much ...